Conventional display units, which display composite images resulting from combining monomedia such as moving pictures, text/graphics and still pictures, offer easy-to-see composite video display to viewers by changing display attributes of uninterested windows such as reducing luminance or frame rate or size of uninterested windows to mitigate eyestrain or the like as disclosed in Japanese patent application laid-open No. 2001-175239, for example.
With the foregoing configuration, the conventional display unit has a problem of being likely to make low image quality display unintended by a producer of the contents or a user of a personal computer who instructs to present the windows on the entire screen, because the display unit changes the display attributes of the uninterested windows such as lowering the luminance or frame rate, or reducing the window size.
The present invention is implemented to solve the foregoing problem. Therefore it is an object of the present invention to provide a display unit capable of achieving high quality image display just as intended by a person who instructs to present the windows on the entire screen by setting a certain region of interframe difference as a window of interest and by carrying out image enhancing processing of the window of interest.